1. Field of the Invention
Embodiments relate to a liquid crystal display (LCD) apparatus including a source driver and a time controller. More particularly, embodiments relate to a LCD apparatus that can reuse intellectual property (IP) blocks therein.
2. Description of the Related Art
A conventional LCD apparatus may include a time controller, a plurality of source drivers, and a display panel. The time controller receives image data as first data, temporarily stores the first data, determines the time and location at which the first data is output, and outputs a plurality of pieces of second data. The time controller also includes a clock output unit that outputs a clock signal used to transfer the plurality of pieces of second data.
The source drivers receive the second data and the clock signal, convert the second data into analog signals, and output the analog signals to the display panel. The display panel displays an image according to the output signals of the source drivers.
In the conventional LCD apparatus, the clock output unit and the plurality of source drivers are connected to each other in a multi-drop fashion. However, when a clock signal is transferred in the multi-drop fashion to a source driver distant from the clock output unit the clock signal may be distorted. Also, when a clock signal is transmitted in the multi-drop fashion and a plurality of pieces of second data signal are transferred in synchronization with the clock signal to a source driver, electromagnetic interference (EMI) may occur in the second data signal.
The plurality of pieces of second data are transmitted concurrently from the time controller to the source drivers via signal lines which are connected to each other in the multi-drop fashion. Since the plurality of pieces of second data is transmitted in synchronization with a single clock signal, the plurality of pieces of second data are transmitted with the same timing.
Since a plurality of pieces of second data are concurrently transmitted to the respective source drivers, differential current required for data transmission is applied once at the same time. Accordingly, since current is abruptly required, system stability deteriorates. Also, since data is simultaneously applied to adjacent source drivers, EMI may be significant.
Further, in the conventional LCD apparatus, when the time controller receives the first data and outputs the second data, operating conditions, e.g., data loading times, charge sharing times, etc., for the respective data need to be set separately. In other words, a separate circuit for setting the operating conditions has to be installed in the conventional LCD apparatus.
Also, if display settings, e.g., a resolution, a color depth, the number of channels of each source driver, etc., are varied, the conventional LCD apparatus cannot reuse existing IP blocks. Here, the term ‘IP blocks’ means functional blocks (semiconductor design modules) manufactured together when the corresponding integrated circuit (IC) is designed, have independent functions, and can be reused. That is, IP blocks are blocks in which functions required to configure logic circuits of a semiconductor are integrated into hardware or software. The source drivers, components in the time controller, etc., may be IP blocks.
Since the conventional LCD apparatus transmits a clock signal through signal lines which are connected to the source drivers in the multi-drop fashion, EMI may be significant. Also, since data is concurrently transferred to all source drivers, system stability deteriorates. Furthermore, whenever a LCD apparatus, source drivers, etc. are replaced, existing IP blocks need to be replaced.